• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.1048-1053
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• 2009

The present study was conducted to determine the effects of chitosan on nitric oxide (NO) content and inducible nitric oxide synthase (iNOS) activity in serum, and relative expression of iNOS mRNA in the duodenum, jejunum, and ileum of broiler chickens. A total of 240 one-day-old Arbor Acre mixed-sex broiler chickens were randomly allotted to six dietary treatments with five replicates in each treatment and eight chickens in each replicate. The broiler chickens in the six treatments were fed the basal diet supplemented with 0 (control), 0.05, 0.2, 0.5, 1.0 or 2.0 g/kg chitosan. The trial lasted for 42 days. The results showed that dietary chitosan enhanced NO content and iNOS activity in serum as well as iNOS mRNA expression in the duodenum and ileum of broiler chickens in a quadratic dose-dependent manner (p<0.05), and improved jejunum iNOS mRNA expression in a quadratic dose-dependent manner (p<0.10) with increasing addition of chitosan. Chicks fed a diet containing 0.5-1.0 g/kg chitosan had higher NO content and iNOS activity in serum as well as small-intestinal iNOS mRNA expression compared with birds given the control diet, but positive effects of chitosan tended to be suppressed when addition of chitosan in the diet was increased to 2.0 g/kg. These results implied that there was a threshold level of chitosan inclusion beyond which progressive reductions in serum NO content and small intestinal iNOS expression occured, and the regulation of chitosan on immune functions in chickens is probably associated with activated expression of iNOS and NO secretion.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.5
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• pp.283-287
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• 2003

While nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is beneficial for host survival, it is also detrimental to the host. Thus, regulation of iNOS gene expression may be an effective therapeutic strategy for the prevention of unwanted reactions at various pathologic conditions. During the screening process for the possible iNOS regulators, we observed that esculetin is a potent inhibitor of cytokine-induced iNOS expression. The treatment of 3T3-L1 adipocytes with the tumor necrosis factor-${\alpha}$ (TNF) induced iNOS expression, leading to enhanced NO production. TNF-induced NO production was inhibited by esculetin in a dose-dependent manner. Esculetin inhibited the TNF-induced NO production at the transcriptional level through suppression of iNOS mRNA and subsequent iNOS protein expression. These results suggest esculetin, a component of natural products, as a naturally occurring, nontoxic means to attenuate iNOS expression and NO-mediated cytotoxicity.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.511-515
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• 2014

In a screen for plant-derived inhibitors of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells, a flavonol isolated from the chloroform extract of Alpinia officinarum was isolated. The structure of the flavonol was found to be 3,5,7-trihydroxy-2-phenylchromen-4-one (galangin, GLG) by using spectroscopy. GLG exhibited an inhibitory effect ($IC_{50}$ value: $26.8{\mu}M$) on NO production in LPS-stimulated RAW 264.7 murine macrophage cells. Moreover, GLG suppressed expressions of inducible nitric oxide synthase (iNOS) protein and mRNA in a dose-dependent manner.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.2
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• pp.233-239
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• 1998

Stimulated alveolar macrophages and neutrophils produce nitric oxide, a free radical by an inducible nitric oxide synthase(iNOS), which reacts with superoxide anion to form peroxynitrite, a more highly reactive toxic species. The objectives of the present study were to evaluate acute inflammatory lung injury and to determine iNOS mRNA induction and nitric oxide production by rat broncho-alveolar lavage cells following intratracheal treatment of silica. After 4 h exposure to silica, differential counts of broncho-alveolar lavage cells and lactate dehydrogenase(LDH) activity as well as total protein in the broncho-alveolar lavage fluid were determined. Broncho-alveolar lavage cells were also assayed for iNOS mRNA and the productions of nitrite and nitrate measured in the cells cultured. Differential analysis of broncho-alveolar lavage cells showed that the number of alveolar macrophages slightly decreased following silica treatment; however, red blood cells, lymphocytes, and neutrophils significantly were increased by 9-, 14-, and 119-fold following silica treatment, respectively, compared with the saline control. It was also found significant increases in the LDH activity and total protein in the lavage fluid obtained from silica-treated rats, indicating silica-induced acute lung injury. Northern blot analysis demonstrated that the steady state levels of iNOS mRNA in broncho-alveolar lavage cells were increased following silica treatment. The productions of nitrite and nitrate in the cultured cells were significantly increased by 2-fold following silica treatment, respectively, which were attenuated by the NOS inhibitor $N{\omega}-nitro-L-arginine-methyl$ ester(L-NAME) and partially reversed by L-arginine. These findings suggest that nitric oxide production in alveolar macrophages and recruited neutrophils is increased in response to silica. Nitric oxide may contribute in part to acute inflammatory lung injury.

• Archives of Pharmacal Research
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• v.22 no.1
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• pp.55-59
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• 1999

Nitric oxide synthesized by inducible nitric oxide synthase (iNOS) has been implicated as a mediator of inflammation in rheumatic and autoimmune diseases. The effects of higenamine, a tetrahydroisoquinoline compound, on induction of NOS by bacterial lipopolysaccaride (LPS) were examined in murine peritoneal macrophages. LPS-induced nitrite/nitrate production was markedly inhibited by higenamine which at 0.01 mM, decreased nitrite/nitrate levels by $48.7{\pm}4.4%$This was comparable to the inhibition of LPS-induced nitrite/nitrate production by tetrandrin ($49.51{\pm}2.02%$). at the same concentration. Northern and Western blot analysis of iNOS expression demonstrated that iNOS expression was significantly attenuated following co-incubation of peritoneal macrophages with LPS (10 $\mu\textrm{g}$/m;; 18hrs) and higenamine (0.001, 0.,01 mM; 18hrs). These results suggest that higenamine can inhibit LPS-induced expression of iNOS mRNA in murine peritoneal macrophages. The clinical implications of these findings remain to be established.

• Journal of Trauma and Injury
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• v.21 no.2
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• pp.120-127
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• 2008

Purpose: Many studies on the time course of inducible nitric oxide synthase (iNOS) gene expression have been performed in the LPS (Lipopolysaccharide)-induced endotoxemic model, but there have been few experimental approaches to continuous peritonitis-induced sepsis model. We conducted this study to establish basic data for future sepsis-related research by investigating the time course of iNOS gene expression and the relationship with the production of inflammatory mediators in the early sepsis model induced by cecal ligation and puncture (CLP). Methods: Male Sprague-Dawley rats were operated on by sing the CLP method to induce of peritonitis; and then, they were sacrificed and samples of blood and lung tissues were obtained at various times (1,2,3,6,9 and 12 h after CLP). We observed the expression of iNOS mRNA from lung tissues and measured the synthesis of nitric oxide, $IL-1{\beta}$, and $TNF-{\alpha}$ from the blood. Results: iNOS mRNA began to be expressed at 3 h and was maintained untill 12 h after CLP. The nitric oxide concentration was increased significantly at 6 h, reached its peak level at 9 h, and maintained a plateau untill 12 h after CLP. $TNF-{\alpha}$ began to be detected at 3 h, increased gradually, and decreased steeply from 9 h after CLP. $IL-1{\beta}$ showed its peak level at 6 h after CLP, and tended to decrease without significance. Conclusion: We observed that the iNOS gene was expressed later in peritonitis-induced sepsis than in LPS-induced sepsis. Nitric oxide and key inflammatory mediators were also expressed later in peritonitis-induced sepsis than in LPS-induced sepsis.

• Journal of Periodontal and Implant Science
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• v.36 no.2
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• pp.361-373
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• 2006

치주질환의 진행이 나이에 의해 영향을 받는다는 사실은 알려져 있으나 노화에 따른 치주조직 세포의 기능적인 변화에 관한 사실은 많이 알려져 있지 않다. 노화에 따른 세포의 노화가 치주질환의 진행에 어떠한 여향을 끼치는가를 아는 것은 중요하다. 염증 상태에서 nitric oxide (NO)는 조직 파괴에 관여하는 인자로 작용하여 치주질환의 진행에 관여하는 것으로 알려져 있다. 따라서 이 연구는 사람의 치은에서 배양된 치은섬유아세포를 이용하여 세포의 노화에 따른 NO와 이의 합성효소인 inducible nitric oxide synthase (iNOS)의 발현을 알아봄으로써 세포의 노화가 치주질환의 진행에 끼치는 영향에 대해 알아보고자 하였다. 10세의 환자와 55세의 환자에서 각각 채취한 치은에서 배양된 세포와 10세의 환자에서 채취한 세포를 계속적인 계대배양을 통해 얻은 실험실 상 노화된 세포를 포함하여 총 3 종류의 치은섬유세포를 실험에 이용하였다. Hot phenol-water extraction을 통해 추출된 Porphyromonas, gingivalis ATCC 33277 lipopolysaccharide (LPS)와 재조합 $IFN-{\gamma}$ 를 세포에 적용시켜 Griess assay를 통해 조건화된 배지에서 NO를 측정하였다. 20세와 55세의 환자에서 채취된 치은 조직과 총 3 종류의 배양된 세포에 NOS-II 항체를 적용시켜 iNOS 단백질 발현을 관찰하였다. Total RNA를 추출하여 RT-PCR를 통해 iNOS mRNA의 발현을 분석하였다. 치은섬유아세포에서 NO는 자발적으로 발생되었고, 이러한 발현은 젊은 세포보다 노화된 세포에서 강하였다. P, gingivalis LPS와 제조합 $IFN-{\gamma}$는 치은섬유아세포에서 NO의 발현을 증가시켰고, 이러한 발현은 젊은 세포보다 노화된 세포에서 강하였다. 면역조직화학 염색에서 iNOS 단백질은 젊은 사람과 노화된 사람의 치은 조직 모두에서 치은섬유아세포와 상피의 기저층 세포와 염증세포에서 발현되었으나 노화에 따른 발현의 차이를 구별할 수는 없었다. 세포의 면역염색에서 iNOS 단백질은 노화된 세포에서 강하게 발현되었고 이러한 발현은 LPS와 $IFN-{\gamma}$ 에 의해 강화되었다. LPS와 $INF-{\gamma}$ 의 조건이 주어지지 않은 상태에서 iNOS mRNA는 젊은 세포에서보다 노화된 세포에서 강하게 발현되었다. 이러한 결과를 통해 세포의 노화가 NO와 iNOS 발현을 증가시킴으로서 치주질환의 진행에 영향을 끼칠 수 있음을 시사하였다.

• YAKHAK HOEJI
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• v.48 no.2
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• pp.159-164
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• 2004

Primary pro-inflammatory cytokines are a trio: tumor necrosis- $\alpha$ (TNF-$\alpha$), interleukine-$\beta$ (IL-$\beta$), and interleukine-6 (IL-6). These cytokines initiate and regulate the acute-phase inflammatory response during infection, trauma, or stress and appear to play an important role in the immune process. Nitric oxide (NO) is a multi-functional mediator, which plays an important role in regulating various biological functions in vivo. NO production by inducible nitric oxide synthase (iNOS) in macrophages is essential for the defense mechanisms against microorganisms and tumor cells. However, over-expression of iNOS by various stimuli, resulting in over-production of NO, contributes to the pathogenesis of septic shock and some inflammatory and auto-immune disease. Solvent fractions of sage ( Salvia officinalis L.), which is cultivated in Jeju-Do, was assayed for their effects on TNF-$\alpha$ and IL-6 production in LPS-stimulated RAW 264.7 macrophages. Hexane and ethylacetate (EtOAc) fraction of sage inhibited the protein and mRNA expression of TNF-$\alpha$ and IL-6 in LPS stimulated RAW 264.7 cells at the concentration of 100 $\mu\textrm{g}$/$m\ell$. Also, incubation of RAW 264.7 cells with the fraction of hexane or EtOAc (50 $\mu\textrm{g}$/$m\ell$) inhibited the LPS induced nitrite accumulation and the LPS/IFN-${\gamma}$ induced iNOS protein. And this inhibition of iNOS protein is concordant with the inhibition of iNOS mRNA expression. Above results suggest that extract of sage may have anti-inflammatory activity through the inhibition of pro-inflammatory cytokines (TNF-$\alpha$, IL-1$\beta$, IL-6), iNOS and NO.

• Natural Product Sciences
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• v.23 no.2
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• pp.92-96
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• 2017

A sesquiterpene was purified from Artemisia iwayomogi methanolic extract during the course of searching anti-inflammatory principle from medicinal plants. A sesquiterpene identified as armefolin inhibited the production of nitric oxide (NO) and attenuated inducible nitric oxide synthase (iNOS) protein level in lipopolysaccharide (LPS)-activated RAW 264.7 cells. Armefolin also down-regulated mRNA expressions of iNOS and pro-inflammatory cytokines, interleukin-$1{\beta}$ and interleukin-6 in LPS-activated macrophages. Moreover, armefolin suppressed the degradation of inhibitory-${\kappa}B{\alpha}$ (I-${\kappa}B{\alpha}$) in LPS-activated macrophages. These data suggest that armefolin from A. iwayomogi can suppress the LPS-induced production of NO and the expression of iNOS gene through inhibiting the degradation of I-${\kappa}B{\alpha}$. Taken together, armefolin from A. iwayomogi might be a candidate as promising anti-inflammatory agent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1685-1690
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• 2009

In this study, we investigated the effect of C. zawadskii extract on nitric oxide (NO) production, prostaglandin E2 (PGE2) production, protein and mRNA expression of inducible nitric oxide synthase (iNOS) in LPS-induced RAW 264.7 macrophage cells. C. zawadskii extract (5~50 μg/mL) significantly inhibited LPS-induced NO production in a concentration-dependent manner ranging from 23.3% to 100%. Consistent with the inhibitory effect on NO production, C. zawadskii extract inhibited the protein expression and mRNA expression of iNOS. Although flower extracts of C. zawadskii was not effective on the expression of PGE2 and COX-2, flower extracts of C. zawadskii, however, showed a strong anti-inflammatory activity through inhibition of NO production and iNOS expression. The present results suggest that C. zawadskii extract has an inhibitory effect on NO production, and thus can be used as an anti-inflammatory agent.